1. Field of Invention
The present invention relates to video processing, and more particularly to a scalar and video processing method wherein pixel data of the scaled images are provided using two clock signals having different frequencies.
2. Description of Related Art
Graphics systems often display images on display screens. For example, a computer system may display the image of an object on a flat-panel monitor. Television systems and cameras are some of the other examples of such graphics systems. To achieve the display of an image, the image is generally represented by image data, and display signals are generated from the image data. The display signals cause the image to be displayed on a corresponding display screen.
During such a display, a graphics system may need to scale (either upscale or downscale) the image. A method for scaling the image is provided in U.S. Pat. No. 5,739,867 (hereinafter, the '867). By using the '867, a source image could be upscaled in both vertical and horizontal directions to generate a destination image frame. The upscaling can be performed without maintaining the aspect ratio of the source image as required in the specific context. Aspect ratio of an image generally refers to the ratio of the length of the image to the width of the image. The '867 can upscale images without having to maintain the aspect ratio of the source image. Accordingly, a user typically has the option of specifying the length and breadth of the destination image without regard to the aspect ratio of the source image.
However, the increased pixel data resulting from the up-scaling necessitate a clock signal for outputting the destination images having a frequency higher than that for receiving the source images. The high-frequency destination clock signal induces a high power consumption which is a critical disadvantage in circuit design.